1. Field of Invention
The present invention relates to a timing controller and a timing control method of a liquid crystal panel, and more particularly to a clip system and a timing clip control method, capable of providing a base working signal and a clip voltage of the same signal information before and after a frame rate of a system signal changes.
2. Related Art
Currently, requirements of energy saving of electronic devices have become one of major criteria in design performed by manufacturers, which is also true to active matrix displays, such as liquid crystal displays and Organic Light-Emitting Diode (OLED) displays. Therefore, manufacturers research and develop a method for decreasing power consumption of a display in various operating environments by adjusting a frame rate of a working signal. For example, during working, a frame rate of a base working signal provided by a timing controller of a display is 60 Hz, and during a standby period, the frame rate of the base working signal provided by the timing controller is 40 Hz, and a charging time length of each liquid crystal element is longer than that in the environment in which the frame rate is 60 Hz.
Additionally, during working, a base working signal is transmitted to each gate line one by one to open a semiconductor channel layer of a Thin Film Transistor (TFT) element that controls charging time of a liquid crystal unit connected to the gate line, so that a pixel data signal can be transmitted to a drain from a source after passing through the opened semiconductor layer, and charge the liquid crystal unit. When each of the arranged liquid crystal units is charged, the base working signal is affected by electric impedance caused by the liquid crystal units of a increasing number and through which the base working signal passes, such that a waveform of the base working signal deforms gradually, thus resulting in inconsistent charging charges of the liquid crystal units in the process. Therefore, the manufacturers dispose a clip module between the timing controller and the gate driver circuit, and the clip module is used to clip the base working signal so as to alleviate the influence from the electric impedance of the liquid crystal unit and maintain a voltage waveform of the base working signal provided to the liquid crystal unit, thus balancing the charging charges of the liquid crystal units.
However, after the frame rate is switched, the charging time lengths of the liquid crystal elements become inconsistent, which varies the imaging luminance of a liquid crystal panel, thus resulting in screen transient flickering. In addition, the change of the frame rate results in an inconsistent waveform of a clip voltage generated by a clip module, which leads to inconsistent charging power of charging charges, thus resulting in deteriorated screen transient flickering.